alistair23-linux/drivers/gpu
Laurent Pinchart 6a00a4221a drm: rcar-du: Restrict DPLL duty cycle workaround to H3 ES1.x
The H3 ES1.x exhibits dot clock duty cycle stability issues. We can work
around them by configuring the DPLL to twice the desired frequency,
coupled with a /2 post-divider. This isn't needed on other SoCs and
breaks HDMI output on M3-W for a currently unknown reason, so restrict
the workaround to H3 ES1.x.

From an implementation point of view, move work around handling outside
of the rcar_du_dpll_divider() function by requesting a x2 DPLL output
frequency explicitly. The existing post-divider calculation mechanism
will then take care of dividing the clock by two automatically.

While at it, print a more useful debugging message to ease debugging
clock rate issues.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
2017-08-03 16:17:23 +03:00
..
drm drm: rcar-du: Restrict DPLL duty cycle workaround to H3 ES1.x 2017-08-03 16:17:23 +03:00
host1x Linux 4.12-rc7 2017-06-27 08:28:30 +10:00
ipu-v3 drm: Convert to using %pOF instead of full_name 2017-07-26 13:45:06 +02:00
vga sched/wait: Rename wait_queue_t => wait_queue_entry_t 2017-06-20 12:18:27 +02:00
Makefile